Megalobrachium garthi Haig, 1957

Ferreira, Luciane Augusto De Azevedo & Anker, Arthur, 2021, An annotated and illustrated checklist of the porcelain crabs of Panama (Decapoda: Anomura), Zootaxa 5045 (1), pp. 1-154 : 25-26

Megalobrachium garthi Haig, 1957

( Fig. 7 )

Pachycheles rotundus Milne Edwards & Bouvier 1894: 291 (nomen nudum).

Megalobrachium garthi Haig 1957a: 39 , pl. 10, figs. 1–5; Haig 1957b: 14; Haig 1960: 220, pl 16, fig. 7, pl. 39, fig. 4; Haig et al. 1970: 24; Lazarus-Agudelo & Cantera-Kintz 2007: 229; García-Madrigal & Andréu-Sánchez 2009: 27, fig. 2B; Hiller & Lessios 2019: 414, fig. 1h.

Material examined. None from Panama. Extra-limital material. Colombia [Pacific]: 1 male, cl 3.4, cw 3.1 (CRBM- UV-cr:2009-107), Los Negritos off Bahía Málaga, 03°53’47.5”N, 77°24’09.8”W, depth 2.5–3 m, sand and rock bottom, ARMS, leg. J.F. Lazarus-Agudelo et al., 27.04.2009 (fcn COL-275) .

Previous records from Panama. Haig (1960).

Distribution. East Pacific: Mexico, Panama (Secas Is.) and Colombia ( Haig 1960; present study).

Ecology. Rocky intertidal and shallow subtidal, known depth range: 0–8 m; under rocks or on sponges and corals ( Haig 1957b; Lazarus-Agudelo & Cantera-Kintz 2007; García-Madrigal & Andréu-Sánchez 2009).

Remarks. According to Haig (1960), M. garthi is superficially similar to another eastern Pacific species, M. sinuimanus ( Lockington, 1878) , especially in having a mesial lobe on the P1 carpus; in fact, they were recently confirmed to be sister species (Hiller & Lessios 2019). However, M. garthi ( Fig. 7 , showing a specimen from Bahía Málaga, Colombia) can be readily distinguished from M. sinuimanus , a species confined to the Pacific coast of Mexico from the Gulf of California to Oaxaca ( García-Madrigal & Andréu-Sánchez 2009), by the presence of small granules covering the carapace and P1–P4, as well as by the five-plated telson.

Figures

FIGURE 7. Megalobrachium garthi Haig, 1957: extra-limital specimen, male (cl 3.4 mm, cw 3.1 mm) from Los Negritos off Bahía Málaga, Colombia (CRBM-UV-cr:2009-107), dorsal view [photograph by AA].